Compound clamps having perpendicular first and second clamping components are useful in carpentry. Therefore, compound clamps have been provided with perpendicular first and second clamping components. The first clamping component applies a force along a first clamping axis to securely hold one or more work pieces together. The second clamping component applies a force along a second clamping axis perpendicular to the first clamping axis to secure an additional work piece to the first work piece(s). Examples of such clamps are disclosed in U.S. Pat. No. 242,959 to Naglee and U.S. Pat. No. 1,402,621 to Knittel and Kesslering.
Compound clamps are particularly useful in the fabrication of countertops. For example, in fabricating a length of countertop, typically a single finished sheet is adhered to a countertop frame to cover its upper surface. It is advantageous to adhere a finished edge strip or facing to the countertop frame at the same time. Thus, a first clamping component may be used to secure a finished surface sheet to a countertop frame while the perpendicular clamping component is used to secure a finished edge strip to the countertop frame. In such a use, it is necessary for the second clamping component to be translationally adjustable along the first clamping axis so that the second clamping force may be applied to the appropriate area depending on the relative size, shape and desired position of the various work pieces.
A problem exists with the clamps disclosed in the above patents. The first clamping component of each of these clamps includes two opposed coaxial clamping screws which provide a force for clamping in a first clamping axis. Translational adjustability of the second clamping component along the first clamping axis can only be achieved by reciprocal adjustment of the two clamping screws. Adjustment in this manner is undesirable because threading is a relatively slow process especially since both clamping screws must be turned separately and in a reciprocal fashion.
This is particularly a problem in the fabrication of countertops because the large surface area to be clamped typically requires many clamps to secure the finished sheets until the adhesives set. Typically adhesives used to bond the sheets to the countertop frames become tacky very rapidly and can prevent realignment of the finished surfaces after a short time. Therefore, time spent in adjusting each clamp is critical.
Other solutions have been proposed to solve this problem with some degree of success. For example, U.S. Pat. No. 2,642,905 to Hewat and U.S. Pat. No. 1,788,546 to Schmieder disclose clamps which provide for a second clamping component which is perpendicular to a first clamping component and is translationally adjustable along an axis thereof. However, a problem exists in the clamps disclosed by both Hewat and Schmieder.
For example, the clamp disclosed by Hewat includes a frame member having a slot disposed through a longitudinal portion thereof. The second clamping component includes a threaded clamping screw carried in a generally cylindrical support member which is made adjustable along the support frame by means of a pin extending from one side of the support member through the slot and slidable therein. Thus, the clamping screw of the second clamping component is mounted to the side of the frame. This configuration results in clamping force being directed along a clamping axis which is beside the frame and out of a plane defined by the first clamping component. This causes a moment or torque about the frame which can cause the entire clamp to twist. Once the clamp twists, the second clamping component is directed at an angle to the work piece.
The device of Schmieder suffers from the same problem because its similar configuration provides that a perpendicular clamping screw is mounted to the side of a frame or standard. The twisting of these clamps is particularly a problem where finished sheets are adhesively bonded to a countertop frame. When the clamp twists, the finish sheets will tend to slide on the adhesive. This is particularly true of any edge or face strips engaged by the second clamping component because the second clamping component becomes angled with respect to the face strip after the clamp twists. When working with countertop materials such as CORIAN.TM., adhesives used tack rapidly and set on the order of 30 to 45 minutes. Thus, any sliding of the work pieces can cause disastrous results as they may become permanently adhered to the work piece in an incorrect position.
The present invention provides a solution to this problem as well as providing a quick and easy to use clamp for general work and particularly, the fabrication of countertops.